Preheat the oven to 350°F (175°C).

In a mixing bowl, combine sliced peaches, 1/2 cup sugar, lemon juice, cornstarch, and cinnamon. Toss to coat the peaches evenly.

Pour the peach mixture into a greased baking dish.

In another bowl, whisk together flour, remaining sugar, baking powder, and salt.

Stir in milk and melted butter until just combined.

Pour the batter over the peach filling in the baking dish.

Bake in the preheated oven for 40-45 minutes or until the topping is golden brown and a toothpick inserted comes out clean.

Let cool for a few minutes before serving.